Dialects are a specific form of geographic variation of birdsong with relatively sharp boundaries between distinct song characteristics,which provide opportunities for focused studies of processes underlying the emerg...Dialects are a specific form of geographic variation of birdsong with relatively sharp boundaries between distinct song characteristics,which provide opportunities for focused studies of processes underlying the emergence of spatial patterns in vocalization.Several songbird species that exhibit dialects became models for such research,and for some of them large-scale datasets were assembled that included recordings provided by the public.Among them,the Yellowhammer(Emberiza citrinella,Emberizidae) is particularly prominent,as it has been recently a subject of dedicated citizen science projects focusing on its dialect distribution.The most successful,in terms of public participation as well as the number and density of obtained recordings,was the Dialects of Czech Yellowhammers(DCY) project,which assembled detailed data at the whole-country level.A mosaic of almost all common song variants known across Europe was observed in Czechia,but the results indicated that some of the traditionally recognized Yellowhammer dialects may not represent geographically clustered song variants,at least not in Central Europe.We quantitatively analysed variation(frequency and temporal characteristics and modulation) of the terminal song element in three dialects defined by arbitrary frequency thresholds in DCY.Multivariate analyses indicated that pooling these to two distinct groups reflects the variation in the songs,as well as their spatial distribution,better than retaining the current classification to three dialects or their finer splitting to even more categories.We provide simple measures that may be used for classification of these Yellowhammer song variants in Central Europe.However,we warn from indiscriminate transposing of results from one region to another,as that may lead to substantial biases.Future studies of birdsong variation will benefit from big data assembled by citizen scientists,but to maximise their usefulness for further dialect research,careful delineation of dialect boundaries is essential.展开更多
Although the aetiology of inflammatory bowel disease (IBD) remains unknown, the pathogenesis is gradually being unravelled, seeming to be the result of a combination of environmental, genetic, and immunological factor...Although the aetiology of inflammatory bowel disease (IBD) remains unknown, the pathogenesis is gradually being unravelled, seeming to be the result of a combination of environmental, genetic, and immunological factors in which an uncontrolled immune response within the intestinal lumen leads to inflammation in genetically predisposed individuals. Multifactorial evidence suggests that a defect of innate immune response to microbial agents is involved in IBD. This editorial outlines the immunopathogenesis of IBD and their current and future therapy. We present IBD as a result of dysregulated mucosal response in the intestinal wall facilitated by defects in epithelial barrier function and the mucosal immune system with excessive production of cytokines growth factors, adhesion molecules, and reactive oxygen metabolites, resulting in tissue injury. Established and evolving therapies are discussed in the second part of this editorial and at the end of this section we review new therapies to modulate the immune system in patients with IBD.展开更多
AIM: To analyze the relationship between perisinusoidal stellate cell (PSC) activation and the dietary fat quantity and composition in the treatment of hepatic steatosis.METHODS: Using an experimental rat model of ste...AIM: To analyze the relationship between perisinusoidal stellate cell (PSC) activation and the dietary fat quantity and composition in the treatment of hepatic steatosis.METHODS: Using an experimental rat model of steatosis based on the intake of a hyperlipidic diet (14% fat as olive oil or sunflower oil, HL-O and HL-S, respectively), we analyzed the liver's capability of recovery after the treatment with a normal-lipidic diet (5% fat as olive oil or sunflower oil, NL-O and NL-S, respectively) by immunocytochemical and Western blot analysis of glial fibrillary acidic protein (GFAP) expression in PSCs, collagen quantification and serum aminotransferase determination.RESULTS: The fatty infiltration in the steatotic livers decreased after the treatment with both NL diets, indicating liver recovery. This decrease was accompanied with a lower collagen deposition and aminotransferase level as well as changes in the PSC population that increased the GFAP expression. The above-mentioned effects were more pronounced in animals fed on NL-O based diet. CONCLUSION: Treatment with a balanced dietenriched in olive oil contributes to the liver recovery from a stea totic process. The PSC phenotype is a marker of this hepatic-recovery model.展开更多
The objective of this study was to compare ecophysiological and morphological parameters of a regionally endangered orchid species,Epipactis atrorubens(Hoffm.ex Bernh.)Bess.,growing in two forest communities(on serpen...The objective of this study was to compare ecophysiological and morphological parameters of a regionally endangered orchid species,Epipactis atrorubens(Hoffm.ex Bernh.)Bess.,growing in two forest communities(on serpentine and granite outcrops)of the Middle Urals,Russia.Biodiversity,dominance,and phytocoenosis studies showed the colonization of a wide range of plant species on both sites.The physicochemical properties of the soil,chemical composition and morphological features of E.atrorubens,growing under technogenic conditions(asbestos deposits),on serpentine outcrops and in the natural environment of the granite massif were studied for the first time.The serpentine substrate differed from the granite one by its greater stoniness,circumneutral pH and lower contents of available nitrogen and phosphorus.Extremely high concentrations of magnesium were found in the serpentine soil,some 79 times higher than in the granite substrate.High concentrations of nickel(94 times),chromium(59 times),cobalt(17 times),and iron(4 times)were found in the serpentine substrate,higher than in the granite substrate.The differences between the sites for available metal contents and for root and shoot metal contents were significantly less.Concentrations of most of the metals in the roots were higher than in the shoots.Despite higher metal concentrations and lower nitrogen and phosphorus levels in serpentine soils,E.atrorubens had a larger population and greater viability compared to those growing on granite.Plants on serpentine outcrops were characterized by the formation of a larger number of fruits,greater root lengths and thicker leaf blades,compared to plants on granites.The well-developed orchid mycorrhizae contributed to the survival of this species under unfavorable serpentine conditions.Hence,serpentine outcrops formed due to the mining of asbestos could be a suitable substrate for the light-demanding E.atrorubens due to its capacity to adapt to dry,rocky,nutrient-depleted soils and limited competition from other plants.展开更多
Recent findings suggest that apoptotic protein apoptosis-inducing factor (AIF) may also play an important non-apoptotic function inside mitochondria. AIF was proposed to be an important component of respiratory chain ...Recent findings suggest that apoptotic protein apoptosis-inducing factor (AIF) may also play an important non-apoptotic function inside mitochondria. AIF was proposed to be an important component of respiratory chain complex I that is the major producer of superoxide radical. The possible role of AIF is still controversial. Superoxide production could be used as a valuable measure of complex I function, because the majority of superoxide is produced there. Therefore, we employed superoxide-specific mitochondrial fluo- rescence dye for detection of superoxide production. We studied an impact of AIF knockdown on function of mitochondrial complex I by analyzing superoxide production in selected cell lines. Our results show that tumoral telomerase-positive (TP) AIF knockdown cell lines display significant increase in superoxide pro- duction in comparison to control cells, while a non-tumoral cell line and tumoral telomerase-negative cell lines with alternative lengthening of telomeres (ALT) show a decrease in superoxide production. According to these results, we can conclude that AIF knockdown disrupts function of complex I and therefore increases the superoxide production in mitochondria. The distinct effect of AIF depletion in various cell lines could result from recently discovered activity of telomerase in mitochondria of TP cancer cells, but this hypothesis needs further investigation.展开更多
Atrial fibrillation(AF) is the most commonly encountered clinical arrhythmia associated with pronounced mortality and morbidity, which are related to palpitations, fainting, congestive heart failure, and stroke. Prolo...Atrial fibrillation(AF) is the most commonly encountered clinical arrhythmia associated with pronounced mortality and morbidity, which are related to palpitations, fainting, congestive heart failure, and stroke. Prolonged episodes of AF promote AF persistence mainly due to electrical remodelling that alters ion-channel expression and/or function. Micro RNAs(mi RNAs), a new class of noncoding mR NAs of around 22 nucleotides in length, have recently emerged as one of the key players in the geneexpression regulatory networks. The potential roles of miR NAs in controlling AF have recently been investigated. Several recent studies have provided promising results for a better understanding of the molecular mechanisms of AF. In this review, we summarize the mechanism of miR NAs as regulators of ion-channel gene expression and their role in causing AF through electrical remodelling.展开更多
Celiac disease (CD) is a common autoimmune disorder characterized by an immune response to ingested gluten and has a strong HLA association with HLA- DQ2 and HLA-DQ8 molecules, but human HLA-DQ risk factors do not exp...Celiac disease (CD) is a common autoimmune disorder characterized by an immune response to ingested gluten and has a strong HLA association with HLA- DQ2 and HLA-DQ8 molecules, but human HLA-DQ risk factors do not explain the entire genetic susceptibility to gluten intolerance. CD is caused by the lack of immune tolerance (oral tolerance) to wheat gluten. In this sense, the expression of soluble HLA-G in CD is of special interest because the molecule plays an important role in the induction of immune tolerance. The enhanced expression of soluble HLA-G found in CD may be part of a mechanism to restore the gluten intolerance. In this editorial, we review recent progress in understanding CD in relation to its prevalence, diagnosis and possible mechanisms of pathogenesis.展开更多
Wheat streak mosaic virus(WSMV)has become a re-emerging pathogen in cereal crops in the Czech Republic.WSMV was first reported in the former Czechoslovakia in the early 1980s,and then no record of the virus was docume...Wheat streak mosaic virus(WSMV)has become a re-emerging pathogen in cereal crops in the Czech Republic.WSMV was first reported in the former Czechoslovakia in the early 1980s,and then no record of the virus was documented until 2009.The incidence of the virus was recorded in recent years in several winter wheat fields and many grass species.Here,we surveyed the incidence of WSMV in cereal crops.The results demonstrated the existence of the virus in winter wheat and volunteer wheat during each year of the monitoring period,which spanned from 2013–2016.Although the range of infected samples was low(6.4%of the total tested samples),a high incidence of well-distributed virus was recorded.In at least six fields,the virus reached severe and potentially epidemic levels.In accordance with our previous report detailing WSMV infection of native grasses,we tested several grass species commonly grown in the Czech Republic.We found that some grass species acted as experimental hosts and possible reservoirs of the virus;these included Anthoxanthum odoratum(sweet vernal grass),Arrhenatherum elatius(false oat-grass),Lolium multiflorum(Italian rye-grass),Bromus japonicus(Japanese chess),Echinochloa crus-galli(barnyard grass),Holcus lanatus(meadow soft grass)and Holcus mollis(creeping soft grass).Some of these grass species are also important weeds of cereals,which may be the potential source of WSMV infection in cereal crops.Several widely used winter wheat cultivars were tested in the field after artificial inoculation with WSMV to evaluate virus titre by RT-qPCR.Overall,the tested cultivars had a low virus titre,which is associated with mild disease symptoms and may provide a good level of crop resistance to WSMV.展开更多
The possibility of associative learning in plants is a topic of ongoing controversy.In one published study,growing pea plants were reported to associate two stimuli(airflow and light)and thereafter use one(airflow)as ...The possibility of associative learning in plants is a topic of ongoing controversy.In one published study,growing pea plants were reported to associate two stimuli(airflow and light)and thereafter use one(airflow)as an indicator for the other(light),similar to dogs in Pavlov’s famous experiments.However,this observation could not be independently repeated.Here we examine a possible reason for the failure of a published reproduction attempt,which used substantially different light quality during plant cultivation prior to experimental treatments than in the original study.This could have resulted in dramatically different growth characteristics.While the relevance of the original report of plant associative learning remains questionable,greater attention should be paid to good documenting and standardizing the light conditions,in particular spectral quality,not only in studies of plant learning and memory,but also in other areas of experimental plant biology.展开更多
Atrial fibrillation(AF)is the most frequent arrhythmogenic syndrome in humans.With an estimate incidence of1%-2%in the general population,AF raises up to almost10%-12%in 80+years.Thus,AF represents nowadays a highly p...Atrial fibrillation(AF)is the most frequent arrhythmogenic syndrome in humans.With an estimate incidence of1%-2%in the general population,AF raises up to almost10%-12%in 80+years.Thus,AF represents nowadays a highly prevalent medical problem generating a large economic burden.At the electrophysiological level,distinct mechanisms have been elucidated.Yet,despite its prevalence,the genetic and molecular culprits of this pandemic cardiac electrophysiological abnormality have remained largely obscure.Molecular genetics of AF familiar cases have demonstrated that single nucleotide mutations in distinct genes encoding for ion channels underlie the onset of AF,albeit such alterations only explain a minor subset of patients with AF.In recent years,analyses by means of genome-wide association studies have unraveled a more complex picture of the etiology of AF,pointing out to distinct cardiac-enriched transcription factors,as well as to other regulatory genes.Furthermore a new layer of regulatory mechanisms have emerged,i.e.,post-transcriptional regulation mediated by non-coding RNA,which have been demonstrated to exert pivotal roles in cardiac electrophysiology.In this manuscript,we aim to provide a comprehensive review of the genetic regulatory networks that if impaired exert electrophysiological abnormalities that contribute to the onset,and subsequently,on self-perpetuation of AF.展开更多
In this study,we focus on the alteration of the programmed cell death 1(PD-1)/PD-L1 pathway in celiac disease.We discuss the diverse roles of the PD-1 pathway in regulating immune responses and how this knowledge can ...In this study,we focus on the alteration of the programmed cell death 1(PD-1)/PD-L1 pathway in celiac disease.We discuss the diverse roles of the PD-1 pathway in regulating immune responses and how this knowledge can improve celiac disease(CD)autoimmunity.The PD-1 and PD-L1 levels in the serum and in intestinal biopsies of CD patients may be relevant to the determination of a possible correlation between markers of the autoimmune response,inflammation,and disease activity.展开更多
The phytohormone auxin triggers root growth inhibition within seconds via a non-transcriptionalpathway.Among members of the TIR1/AFB auxin receptor family,AFB1 has a primary role in this rapidresponse. However, the un...The phytohormone auxin triggers root growth inhibition within seconds via a non-transcriptionalpathway.Among members of the TIR1/AFB auxin receptor family,AFB1 has a primary role in this rapidresponse. However, the unique features that confer this specific function have not been identified.Here we show that the N-terminal region of AFB1, including the F-box domain and residues thatcontribute to auxin binding,is essential and sufficient for its specific role in the rapid response. Substitutionof the N-terminal region of AFB1 with that of TIR1 disrupts its distinct cytoplasm-enriched localizationand activity in rapid root growth inhibition by auxin. Importantly, the N-terminal region of AFB1 isindispensable for auxin-triggered calcium influx, which is a prerequisite for rapid root growth inhibition.Furthermore, AFB1 negatively regulates lateral root formation and transcription of auxin-induced genes,suggesting that it plays an inhibitory role in canonical auxin signaling. These results suggest that AFB1may buffer the transcriptional auxin response, whereas it regulates rapid changes in cell growth thatcontributeto rootgravitropism.展开更多
Aim:The study aims to analyze the effect of long-term incubation of ERα-positive MCF7 breast cancer cells with 4-hydroxytamoxifen(HT)on their sensitivity to tubulin polymerization inhibitor docetaxel.Methods:The anal...Aim:The study aims to analyze the effect of long-term incubation of ERα-positive MCF7 breast cancer cells with 4-hydroxytamoxifen(HT)on their sensitivity to tubulin polymerization inhibitor docetaxel.Methods:The analysis of cell viability was performed by the MTT method.The expression of signaling proteins was analyzed by immunoblotting and flow cytometry.ERαactivity was evaluated by gene reporter assay.To establish hormone-resistant subline MCF7,breast cancer cells were treated with 4-hydroxytamoxifen for 12 months.Results:The developed MCF7/HT subline has lost sensitivity to 4-hydroxytamoxifen,and the resistance index was 2.Increased Akt activity(2.2-fold)and decreased ERαexpression(1.5-fold)were revealed in MCF7/HT cells.The activity of the estrogen receptorαwas reduced(1.5-fold)in MCF7/HT.Evaluation of class Ⅲβ-tubulin expression(TUBB3),a marker associated with metastasis,revealed the following trends:higher expression of TUBB3 was detected in triple-negative breast cancer MDA-MB-231 cells compared to hormone-responsive MCF7 cells(P<0.05).The lowest expression of TUBB3 was found in hormone-resistant MCF7/HT cells(MCF7/HT<MCF7<MDA-MB-231,approximately 1:2:4).High TUBB3 expression strongly correlated with docetaxel resistance:IC_(50)value of docetaxel for MDA-MB-231 cells was greater than that for MCF7 cells,whereas resistant MCF7/HT cells were the most sensitive to the drug.The accumulation of cleaved PARP(a 1.6-fold increase)and Bcl-2 downregulation(1.8-fold)were more pronounced in docetaxel-treated resistant cells(P<0.05).The expression of cyclin D1 decreased(2.8-fold)only in resistant cells after 4 nM docetaxel treatment,while this marker was unchanged in parental MCF7 breast cancer cells.Conclusion:Further development of taxane-based chemotherapy for hormone-resistant cancer looks highly promising,especially for cancers with low TUBB3 expression.展开更多
基金funded by the Charles University Grant Agency (project number 312213)
文摘Dialects are a specific form of geographic variation of birdsong with relatively sharp boundaries between distinct song characteristics,which provide opportunities for focused studies of processes underlying the emergence of spatial patterns in vocalization.Several songbird species that exhibit dialects became models for such research,and for some of them large-scale datasets were assembled that included recordings provided by the public.Among them,the Yellowhammer(Emberiza citrinella,Emberizidae) is particularly prominent,as it has been recently a subject of dedicated citizen science projects focusing on its dialect distribution.The most successful,in terms of public participation as well as the number and density of obtained recordings,was the Dialects of Czech Yellowhammers(DCY) project,which assembled detailed data at the whole-country level.A mosaic of almost all common song variants known across Europe was observed in Czechia,but the results indicated that some of the traditionally recognized Yellowhammer dialects may not represent geographically clustered song variants,at least not in Central Europe.We quantitatively analysed variation(frequency and temporal characteristics and modulation) of the terminal song element in three dialects defined by arbitrary frequency thresholds in DCY.Multivariate analyses indicated that pooling these to two distinct groups reflects the variation in the songs,as well as their spatial distribution,better than retaining the current classification to three dialects or their finer splitting to even more categories.We provide simple measures that may be used for classification of these Yellowhammer song variants in Central Europe.However,we warn from indiscriminate transposing of results from one region to another,as that may lead to substantial biases.Future studies of birdsong variation will benefit from big data assembled by citizen scientists,but to maximise their usefulness for further dialect research,careful delineation of dialect boundaries is essential.
文摘Although the aetiology of inflammatory bowel disease (IBD) remains unknown, the pathogenesis is gradually being unravelled, seeming to be the result of a combination of environmental, genetic, and immunological factors in which an uncontrolled immune response within the intestinal lumen leads to inflammation in genetically predisposed individuals. Multifactorial evidence suggests that a defect of innate immune response to microbial agents is involved in IBD. This editorial outlines the immunopathogenesis of IBD and their current and future therapy. We present IBD as a result of dysregulated mucosal response in the intestinal wall facilitated by defects in epithelial barrier function and the mucosal immune system with excessive production of cytokines growth factors, adhesion molecules, and reactive oxygen metabolites, resulting in tissue injury. Established and evolving therapies are discussed in the second part of this editorial and at the end of this section we review new therapies to modulate the immune system in patients with IBD.
基金Supported by Direction General de Investigation Cientifica y Tecnica, SAF 2003 04398-C02-02, and Junta de Andalucia,CVI-0184
文摘AIM: To analyze the relationship between perisinusoidal stellate cell (PSC) activation and the dietary fat quantity and composition in the treatment of hepatic steatosis.METHODS: Using an experimental rat model of steatosis based on the intake of a hyperlipidic diet (14% fat as olive oil or sunflower oil, HL-O and HL-S, respectively), we analyzed the liver's capability of recovery after the treatment with a normal-lipidic diet (5% fat as olive oil or sunflower oil, NL-O and NL-S, respectively) by immunocytochemical and Western blot analysis of glial fibrillary acidic protein (GFAP) expression in PSCs, collagen quantification and serum aminotransferase determination.RESULTS: The fatty infiltration in the steatotic livers decreased after the treatment with both NL diets, indicating liver recovery. This decrease was accompanied with a lower collagen deposition and aminotransferase level as well as changes in the PSC population that increased the GFAP expression. The above-mentioned effects were more pronounced in animals fed on NL-O based diet. CONCLUSION: Treatment with a balanced dietenriched in olive oil contributes to the liver recovery from a stea totic process. The PSC phenotype is a marker of this hepatic-recovery model.
文摘The objective of this study was to compare ecophysiological and morphological parameters of a regionally endangered orchid species,Epipactis atrorubens(Hoffm.ex Bernh.)Bess.,growing in two forest communities(on serpentine and granite outcrops)of the Middle Urals,Russia.Biodiversity,dominance,and phytocoenosis studies showed the colonization of a wide range of plant species on both sites.The physicochemical properties of the soil,chemical composition and morphological features of E.atrorubens,growing under technogenic conditions(asbestos deposits),on serpentine outcrops and in the natural environment of the granite massif were studied for the first time.The serpentine substrate differed from the granite one by its greater stoniness,circumneutral pH and lower contents of available nitrogen and phosphorus.Extremely high concentrations of magnesium were found in the serpentine soil,some 79 times higher than in the granite substrate.High concentrations of nickel(94 times),chromium(59 times),cobalt(17 times),and iron(4 times)were found in the serpentine substrate,higher than in the granite substrate.The differences between the sites for available metal contents and for root and shoot metal contents were significantly less.Concentrations of most of the metals in the roots were higher than in the shoots.Despite higher metal concentrations and lower nitrogen and phosphorus levels in serpentine soils,E.atrorubens had a larger population and greater viability compared to those growing on granite.Plants on serpentine outcrops were characterized by the formation of a larger number of fruits,greater root lengths and thicker leaf blades,compared to plants on granites.The well-developed orchid mycorrhizae contributed to the survival of this species under unfavorable serpentine conditions.Hence,serpentine outcrops formed due to the mining of asbestos could be a suitable substrate for the light-demanding E.atrorubens due to its capacity to adapt to dry,rocky,nutrient-depleted soils and limited competition from other plants.
基金Grant Agency of the Czech Republic(project number P302/12/G157).
文摘Recent findings suggest that apoptotic protein apoptosis-inducing factor (AIF) may also play an important non-apoptotic function inside mitochondria. AIF was proposed to be an important component of respiratory chain complex I that is the major producer of superoxide radical. The possible role of AIF is still controversial. Superoxide production could be used as a valuable measure of complex I function, because the majority of superoxide is produced there. Therefore, we employed superoxide-specific mitochondrial fluo- rescence dye for detection of superoxide production. We studied an impact of AIF knockdown on function of mitochondrial complex I by analyzing superoxide production in selected cell lines. Our results show that tumoral telomerase-positive (TP) AIF knockdown cell lines display significant increase in superoxide pro- duction in comparison to control cells, while a non-tumoral cell line and tumoral telomerase-negative cell lines with alternative lengthening of telomeres (ALT) show a decrease in superoxide production. According to these results, we can conclude that AIF knockdown disrupts function of complex I and therefore increases the superoxide production in mitochondria. The distinct effect of AIF depletion in various cell lines could result from recently discovered activity of telomerase in mitochondria of TP cancer cells, but this hypothesis needs further investigation.
基金Supported by Grants BFU2012-38111(Ministerio de Economíay Competitividad,Gobierno de Espaa),Nos.CTS-1614,P08-CTS-03878,BIO-302(Junta de Andalucia)and AFM2012-16074(AFM)
文摘Atrial fibrillation(AF) is the most commonly encountered clinical arrhythmia associated with pronounced mortality and morbidity, which are related to palpitations, fainting, congestive heart failure, and stroke. Prolonged episodes of AF promote AF persistence mainly due to electrical remodelling that alters ion-channel expression and/or function. Micro RNAs(mi RNAs), a new class of noncoding mR NAs of around 22 nucleotides in length, have recently emerged as one of the key players in the geneexpression regulatory networks. The potential roles of miR NAs in controlling AF have recently been investigated. Several recent studies have provided promising results for a better understanding of the molecular mechanisms of AF. In this review, we summarize the mechanism of miR NAs as regulators of ion-channel gene expression and their role in causing AF through electrical remodelling.
文摘Celiac disease (CD) is a common autoimmune disorder characterized by an immune response to ingested gluten and has a strong HLA association with HLA- DQ2 and HLA-DQ8 molecules, but human HLA-DQ risk factors do not explain the entire genetic susceptibility to gluten intolerance. CD is caused by the lack of immune tolerance (oral tolerance) to wheat gluten. In this sense, the expression of soluble HLA-G in CD is of special interest because the molecule plays an important role in the induction of immune tolerance. The enhanced expression of soluble HLA-G found in CD may be part of a mechanism to restore the gluten intolerance. In this editorial, we review recent progress in understanding CD in relation to its prevalence, diagnosis and possible mechanisms of pathogenesis.
基金supported by the grants from the Ministry of Agriculture, Czech Republic from projects QJ1230159 (50%) and RO0415 (50%)
文摘Wheat streak mosaic virus(WSMV)has become a re-emerging pathogen in cereal crops in the Czech Republic.WSMV was first reported in the former Czechoslovakia in the early 1980s,and then no record of the virus was documented until 2009.The incidence of the virus was recorded in recent years in several winter wheat fields and many grass species.Here,we surveyed the incidence of WSMV in cereal crops.The results demonstrated the existence of the virus in winter wheat and volunteer wheat during each year of the monitoring period,which spanned from 2013–2016.Although the range of infected samples was low(6.4%of the total tested samples),a high incidence of well-distributed virus was recorded.In at least six fields,the virus reached severe and potentially epidemic levels.In accordance with our previous report detailing WSMV infection of native grasses,we tested several grass species commonly grown in the Czech Republic.We found that some grass species acted as experimental hosts and possible reservoirs of the virus;these included Anthoxanthum odoratum(sweet vernal grass),Arrhenatherum elatius(false oat-grass),Lolium multiflorum(Italian rye-grass),Bromus japonicus(Japanese chess),Echinochloa crus-galli(barnyard grass),Holcus lanatus(meadow soft grass)and Holcus mollis(creeping soft grass).Some of these grass species are also important weeds of cereals,which may be the potential source of WSMV infection in cereal crops.Several widely used winter wheat cultivars were tested in the field after artificial inoculation with WSMV to evaluate virus titre by RT-qPCR.Overall,the tested cultivars had a low virus titre,which is associated with mild disease symptoms and may provide a good level of crop resistance to WSMV.
基金supported by basic institutional funding of scientific activities at the Charles University[Progres Q43].
文摘The possibility of associative learning in plants is a topic of ongoing controversy.In one published study,growing pea plants were reported to associate two stimuli(airflow and light)and thereafter use one(airflow)as an indicator for the other(light),similar to dogs in Pavlov’s famous experiments.However,this observation could not be independently repeated.Here we examine a possible reason for the failure of a published reproduction attempt,which used substantially different light quality during plant cultivation prior to experimental treatments than in the original study.This could have resulted in dramatically different growth characteristics.While the relevance of the original report of plant associative learning remains questionable,greater attention should be paid to good documenting and standardizing the light conditions,in particular spectral quality,not only in studies of plant learning and memory,but also in other areas of experimental plant biology.
基金Supported by A CNIC translational grant(CNIC2006/08)to Franco Dthe University of Jaén on translational biomedicine to Franco D(UJA2013/01)
文摘Atrial fibrillation(AF)is the most frequent arrhythmogenic syndrome in humans.With an estimate incidence of1%-2%in the general population,AF raises up to almost10%-12%in 80+years.Thus,AF represents nowadays a highly prevalent medical problem generating a large economic burden.At the electrophysiological level,distinct mechanisms have been elucidated.Yet,despite its prevalence,the genetic and molecular culprits of this pandemic cardiac electrophysiological abnormality have remained largely obscure.Molecular genetics of AF familiar cases have demonstrated that single nucleotide mutations in distinct genes encoding for ion channels underlie the onset of AF,albeit such alterations only explain a minor subset of patients with AF.In recent years,analyses by means of genome-wide association studies have unraveled a more complex picture of the etiology of AF,pointing out to distinct cardiac-enriched transcription factors,as well as to other regulatory genes.Furthermore a new layer of regulatory mechanisms have emerged,i.e.,post-transcriptional regulation mediated by non-coding RNA,which have been demonstrated to exert pivotal roles in cardiac electrophysiology.In this manuscript,we aim to provide a comprehensive review of the genetic regulatory networks that if impaired exert electrophysiological abnormalities that contribute to the onset,and subsequently,on self-perpetuation of AF.
基金This work was supported by Research group BIO220,Junta de Andalucía.
文摘In this study,we focus on the alteration of the programmed cell death 1(PD-1)/PD-L1 pathway in celiac disease.We discuss the diverse roles of the PD-1 pathway in regulating immune responses and how this knowledge can improve celiac disease(CD)autoimmunity.The PD-1 and PD-L1 levels in the serum and in intestinal biopsies of CD patients may be relevant to the determination of a possible correlation between markers of the autoimmune response,inflammation,and disease activity.
基金the National Institute of General Medical Sciences(NIGMS)with grants to M.E.(R35GM141892)and to W.B.(R01GM127759)by the European Research Council(grant no.803048)M.F.M.P.P.was supported by a long-term postdoctoral fellowship(LT000340/2019 L)by the Human Frontier Science Program Organization.
文摘The phytohormone auxin triggers root growth inhibition within seconds via a non-transcriptionalpathway.Among members of the TIR1/AFB auxin receptor family,AFB1 has a primary role in this rapidresponse. However, the unique features that confer this specific function have not been identified.Here we show that the N-terminal region of AFB1, including the F-box domain and residues thatcontribute to auxin binding,is essential and sufficient for its specific role in the rapid response. Substitutionof the N-terminal region of AFB1 with that of TIR1 disrupts its distinct cytoplasm-enriched localizationand activity in rapid root growth inhibition by auxin. Importantly, the N-terminal region of AFB1 isindispensable for auxin-triggered calcium influx, which is a prerequisite for rapid root growth inhibition.Furthermore, AFB1 negatively regulates lateral root formation and transcription of auxin-induced genes,suggesting that it plays an inhibitory role in canonical auxin signaling. These results suggest that AFB1may buffer the transcriptional auxin response, whereas it regulates rapid changes in cell growth thatcontributeto rootgravitropism.
基金supported by the Ministry of Science and Higher Education of the Russian Federation(agreement No.075-15-2020-789).
文摘Aim:The study aims to analyze the effect of long-term incubation of ERα-positive MCF7 breast cancer cells with 4-hydroxytamoxifen(HT)on their sensitivity to tubulin polymerization inhibitor docetaxel.Methods:The analysis of cell viability was performed by the MTT method.The expression of signaling proteins was analyzed by immunoblotting and flow cytometry.ERαactivity was evaluated by gene reporter assay.To establish hormone-resistant subline MCF7,breast cancer cells were treated with 4-hydroxytamoxifen for 12 months.Results:The developed MCF7/HT subline has lost sensitivity to 4-hydroxytamoxifen,and the resistance index was 2.Increased Akt activity(2.2-fold)and decreased ERαexpression(1.5-fold)were revealed in MCF7/HT cells.The activity of the estrogen receptorαwas reduced(1.5-fold)in MCF7/HT.Evaluation of class Ⅲβ-tubulin expression(TUBB3),a marker associated with metastasis,revealed the following trends:higher expression of TUBB3 was detected in triple-negative breast cancer MDA-MB-231 cells compared to hormone-responsive MCF7 cells(P<0.05).The lowest expression of TUBB3 was found in hormone-resistant MCF7/HT cells(MCF7/HT<MCF7<MDA-MB-231,approximately 1:2:4).High TUBB3 expression strongly correlated with docetaxel resistance:IC_(50)value of docetaxel for MDA-MB-231 cells was greater than that for MCF7 cells,whereas resistant MCF7/HT cells were the most sensitive to the drug.The accumulation of cleaved PARP(a 1.6-fold increase)and Bcl-2 downregulation(1.8-fold)were more pronounced in docetaxel-treated resistant cells(P<0.05).The expression of cyclin D1 decreased(2.8-fold)only in resistant cells after 4 nM docetaxel treatment,while this marker was unchanged in parental MCF7 breast cancer cells.Conclusion:Further development of taxane-based chemotherapy for hormone-resistant cancer looks highly promising,especially for cancers with low TUBB3 expression.
